Nanowires composed of group III-N alloys (e.g., GaN) provide the potential for new semiconductor device configurations such as nanoscale optoelectronic devices. For example, GaN nanowires can provide large bandgap, high melting point, and chemical stability that is useful for devices operating in corrosive or high-temperature environments. The larger bandgap of GaN and its related alloys also allows the fabrication of light sources in the visible range that are useful for displays and lighting applications. In addition, the unique geometry of each nanowire offers the potential to explore new device paradigms in photonics and in transport devices. To fully realize this potential, a scalable process is needed for making high-quality group III-N nanowires and/or nanowire arrays with precise and uniform control of the geometry, position and crystallinity of each nanowire.
Conventional nanowire fabrication is based on a vapor-liquid-solid (VLS) growth mechanism and involves the use of catalysts such as Au, Ni, Fe, or In. Problems arise, however, because these conventional catalytic processes cannot control the position and uniformity of the resulting nanowires. A further problem with conventional catalytic processes is that the catalyst is inevitably incorporated into the nanowires This degrades the crystalline quality of the resulting nanostructures, which limits their applications.
Thus, there is a need to overcome these and other problems of the prior art and to provide high-quality nanowires and/or nanowire arrays, and scalable methods for their manufacturing. It is further desirable to provide nanowire photoelectronic devices and their manufacturing based on the high-quality nanowires and/or nanowire arrays.